<!DOCTYPE html>
<html lang="zh_CN">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>

</body>
<script type="text/javascript">

   /* while (express){
        // 循环语句
    }
    */

   var i = 0;

   while (i < 10){

       console.log('打印输出', i);
       i++; // 要改变变量，使其循环有出口

   }

   console.log('end');

</script>

</html>
